Natamycin (Pimaricin) is a Polyene Antimicrobial.

Under conditions where growth is inhibited, Natamycin does not affect the permeability of yeast cell membranes. Natamycin impedes the initiation phase of vacuole fusion, preventing the joining of separate vacuoles without damaging the barrier function of the vacuolar membrane. It disrupts vacuole morphology within the yeast cells, resulting in the formation of numerous smaller vacuole structures. Natamycin specifically binds to ergosterol on model membranes. It exhibits a lower minimum inhibitory concentration (MIC) for dematiaceous fungi and species of Curvularia. The solubility and stability of Natamycin in aqueous solutions are enhanced through the formation of a complex with γ-cyclodextrin, which also reduces drug side effects without compromising antifungal activity. The MIC90 of both Natamycin and its complex with Natamycin-γ cyclodextrin (Natamycin-γ CyD) is below 0.0313 mg/ml, indicating that γ CyD significantly enhances the antifungal activity of Natamycin, thus affirming the clinical utility of the Natamycin-gamma CyD complex.